Abstract

Earthquakes damage transportation infrastructure. In addition to replacement and repair costs for damage to transportation structures, large earthquakes can increase time delays resulting from a network component's loss of function. Damage to the network can severely disrupt traffic flows for several months or years. The Utah Department of Transportation (UDOT) recognizes the risks posed by these hazards and initiated this analysis. Impacts on road users can be estimated in terms of user costs from travel time delay. This research presents estimated traffic disruption user delay costs resulting from two earthquake scenarios in Utah. The VISUM traffic macro-simulation model was used to estimate the delay-based user costs. Road segments, which are vulnerable yet critical to detour traffic following an earthquake, are prioritized for rehabilitation. Links that are susceptible to damage in one scenario, but critical in carrying detour traffic for the other scenario, are defined as lifelines.